Introduction: Graphics and Principles of Data Visualisation

Julia Schulte-Cloos

University of Marburg

December 1, 2025

Welcome

What makes for a good data visualisation?

Please note up to five key characteristics that make for a good data visualisation.

1️⃣ Why Data Visualization?

2️⃣️ Foundations of the Grammar of Graphics

3️⃣️ Hands on - Fundamentals of ggplot

4️⃣ Advanced Visualizations

5️⃣ Hands on - Advanced ggplot applications

What can you expect to get out of this workshop?

At the end of the workshop, you will be able to…:

Understand the principles of data visualization and best practices
Comprehend the grammar of graphics for creating structured visualizations
Apply the principles of ggplot to design effective data visualizations
Readily create both simple and advanced visualizations
Develop visualizations that incorporate maps and geospatial data
Enhance your graphs and visualizations with advanced styling and textual elements
Design interactive visualizations to engage your audience

any effort to help people understand the significance of data by placing it in a visual context

to explore your own data
- exploratory analysis
- outlier detection
to communicate and report
- …clearly (using good design principles)
- …precisely and accurately (a plot is worth 1000 words)
- …effectively and efficiently
purpose: convey information and make a point (Wilke 2019)
…data rarely speaks for itself
to represent results of statistical analyses

Wilke 2019 (Fundamentals of Data Visualisation)

Try to analyze the famous visualization by Hans Rosling (“Gapminder”) together with your neighbor. Please click on the link to enlarge.

[1] The “Why” (Purpose): What is the main story this graph is trying to tell?

[2] The “What” (Data): What data variables can you identify in the plot?

[3] The “How” (Mapping): How does the graph use visual properties to represent these variables?

05:00

Try to analyze this datajournalism visualization from the German newspaper Die ZEIT together with your neighbor.

[1] The “Why” (Purpose): What is the main story this graph is trying to tell?

[2] The “What” (Data): What data variables can you identify in the plot?

[3] The “How” (Mapping): How does the graph use visual properties to represent these variables?

05:00

➡️ workshop material heavily draws on their excellent workshops and practical materials

Wilke, Claus O. 2019. Fundamentals of Data Visualization: A Primer on Making Informative and Compelling Figures. O’Reilly Media.